---
name: "ig4"
section: "4freebsd"
platform: "linux"
package: "freebsd-manpages"
version: "12.2-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/ig4/4freebsd"
---

# ig4(4freebsd)

Synopsys DesignWare I2C Controller

## NAME

**ig4** – Synopsys DesignWare I2C Controller

## SYNOPSIS

To compile this driver into the kernel, place the following lines into the kernel configuration file:

**device ig4** **device iicbus**

Alternatively, to load the driver as a module at boot time, place the following line in [loader.conf(5)](/loader.conf/5.md):

```
ig4_load="YES"
```

## DESCRIPTION

The **ig4** driver provides access to peripherals attached to an I2C controller.

## HARDWARE

**ig4** supports the I2C controllers based on Synopsys DesignWare IP that can be found in Intel(R) Core(TM) processors starting from the fourth generation, Intel(R) Bay Trail, Apollo Lake SoC families, and some AMD systems.

## SYSCTL VARIABLES

These [sysctl(8)](/sysctl/8.md) variables are available:

- *debug.ig4\_dump*

  This sysctl is a zero-based bit mask. When any of the bits are set, a register dump is printed for every I2C transfer on an **ig4** device with the same unit number.

## SEE ALSO

[iic(4)](/iic/4.md), [iicbus(4)](/iicbus/4.md)

## AUTHORS

The **ig4** driver was written for DragonFly BSD by Matthew Dillon and subsequently ported to FreeBSD by Michael Gmelin ⟨*freebsd@grem.de*⟩.

This manual page was written by Michael Gmelin ⟨*freebsd@grem.de*⟩.